1. Technical Field
The present invention relates to a printing apparatus.
2. Related Art
For example, among ink jet type printers, there is a printer of a type which uses large-sized paper having a paper size of A2 or more. In the ink jet printer for such a large-sized-paper, besides single sheets of paper, so-called roll paper is often used. In addition, in the following, the so-called roll paper which is wound around a roll body, and a portion which is drawn from the roll body is referred to as paper.
At present, the drawing of the paper from the roll body is performed by rotationally driving a transport roller by a paper feed motor (hereinafter also referred to as a PF motor). In addition, the PF motor is controlled and driven by PID control.
As a printer which uses such a roll body, there is a printer which is disclosed in JP-A-2007-290866. Also, as printers which perform the PID control, there are printers which are disclosed in JP-A-2006-240212, JP-A-2003-79177, and JP-A-2003-48351.
Usually, the transport roller is provided spaced a certain distance in a direction in which the paper is supplied from the roll body mounted on a printer main body. Therefore, there is also a case where it is difficult to transport the paper only by the transport roller. Therefore, there is also proposed a printing apparatus in which a roll motor (hereinafter also referred to as an RR motor) which rotationally drives the roll body is provided and rotates the roll body, thereby transporting the paper.
However, in the printing apparatus as described above, in the case of using slippery paper (medium), there is a problem that if the diameter of the medium that is wound around the roll body is reduced, transport precision falls at the time of the start of the feeding of the paper, so that image quality may deteriorate.